For example, it is proposed that a linear motor is used in a printing head and an exposing-scanning head of an office automation machine, and in parts which requires a linear moving accuracy, such as an exposing-scanning device in a medical apparatus.
Particularly, the shaft type linear motor which is disclosed on from page 1 to page 9 and in FIGS. 1-14 in Japanese Patent Application Open to Public No. H09-172767 is suitable for precise conveyance in the office automation machine from the viewpoint of speed performance and space saving. However, as shown in FIG. 18, the linear motor comprises stator 110 and moving member 120 arranged to linearly move along the outer surface of the stator 110. Moving member 120 comprises electro-magnetic coil 121 and bobbin 122 wound in the internal surface of electro-magnetic coil 121. A minute gap between bobbin 122 and the outer surface of pipe shaped member 111 is provided.
In a conventional linear motor, a moving member is wound around a bobbin. Accordingly, the distance between an electro-magnetic coil and a permanent magnet becomes long. Since the distance between the electro-magnetic coil and the permanent magnet is long, a larger permanent magnet is required to obtain predetermined thrust force.
The present invention is proposed to solve the problems described above, and to provide a linear motor and the manufacturing method of the linear motor to increase thrust force having a simple structure with lower cost.